This invention relates to solid oral pharmaceutical formulations of (S)-methyl (1-((4-(3-(5-chloro-2-fluoro-3-(methyl sulfonamido)phenyl)-1-isopropyl-1H-pyrazol-4-yl)pyrimidin-2-yl)amino)propan-2-yl)carbamate (COMPOUND A) and the use of these formulations for treating proliferative diseases, such as solid tumor diseases.
The COMPOUND A has the chemical structure:

Its preparation and its use as an inhibitor of B-RAF for the treatment of proliferative diseases, such as solid tumor diseases, like melanoma and colorectal cancer, are described in WO 2011/025927, which is here incorporated by reference in its entirety.
COMPOUND A is a BCS class II compound exhibiting poor aqueous solubility at weakly acidic and neutral pH which poses a challenge for oral bioavailability and therapeutic effect. The compound exhibits typical weak base solubility characteristics and is highly soluble at low pH, starts to decline at around pH 3.0 and remains low at intrinsic solubility level over the range of neutral pH. Upon emptying from the stomach, COMPOUND A has the tendency to quickly precipitate out of solution due to an abrupt solubility drop in intestinal pH. This significantly reduces COMPOUND A that is available for intestinal absorption. The present invention relates to orally bioavailable pharmaceutical solid dispersion formulations of COMPOUND A.